Hermeus

About Hermeus

Hermeus Corporation is a defense and aerospace company established in 2018 to develop high-Mach and hypersonic aircraft. The founding team—AJ Piplica (CEO), Glenn Case (CTO), Skyler Shuford (COO), and Mike Smayda (CPO)—brings together experience from the commercial spaceflight sector, having previously worked on rocket programs where they honed skills in rapid, hardware-focused development cycles. Based in Atlanta, Georgia, the company is expanding with a new headquarters in El Segundo, California, to transition from prototyping to production. The firm's business model is centered on securing government contracts, primarily with the U.S. Department of Defense, to fund its technology roadmap. Hermeus has attracted significant investment, including a $60 million contract from the U.S. Air Force in 2021 to develop and test its Quarterhorse aircraft and a reusable hypersonic propulsion system. Subsequent funding rounds, including a $350 million Series C in April 2026, have brought its total capital raised to over $500 million and pushed its valuation to $1 billion. Major contracts also include partnerships with the Defense Innovation Unit (DIU) and participation in the Air Force's Advanced Battle Management System (ABMS) initiative. Hermeus's technical strategy involves an iterative series of uncrewed test aircraft to incrementally de-risk technology. The "Quarterhorse" program serves as the primary testbed, with multiple variants designed to validate different aspects of high-speed flight. This rapid prototyping has led to significant milestones, including the first flight of the Mk 1 demonstrator in May 2025 and a supersonic flight of the F-16-sized Mk 2.1 aircraft just a year later. Future Quarterhorse versions will test thermal limits and materials near Mach 3. These demonstrators pave the way for "Darkhorse," a multi-mission, reusable hypersonic drone designed for defense and national security operations. At the core of Hermeus's aircraft is the Chimera engine, a turbine-based combined cycle (TBCC) system that merges a conventional turbojet with a ramjet. This hybrid design allows the aircraft to take off from standard runways using the turbojet (a modified Pratt & Whitney F100) and then transition to the ramjet to achieve speeds above Mach 5. The company successfully demonstrated this critical mode transition in ground tests. While the immediate focus is on defense applications with Darkhorse, the company's long-term vision includes "Halcyon," a 20-seat commercial passenger aircraft capable of flying from New York to London in 90 minutes.